1. Field Of The Invention
The present invention relates to helicopter blade construction and more particularly to an improved helicopter blade apparatus for controlling blade pitch wherein a variable elevation circumferential surface extending around the hub of the craft provides a roller surface that is engaged by roller members attached to a variable pitch flap portion of the helicopter blade. Blade pitch can be modified precisely with respect to the rotational position of the blade so that maximum bite is provided when the helicopter roller blade moves rearwardly with respect to the direction of travel. The flap portion is rotated downwardly, biting into the surrounding air as the blade moves rearwardly. The pitch is minimized and the blade flap, is rotated substantially flat when the blade moves forwardly, i.e. in the same direction as the direction of travel of the craft.
2. General Backoround
Helicopters can be single rotor or multiple rotor craft. A plurality of blades (eg. three to six) are rotatably mounted upon each rotor. The helicopter blade desirably maximizes bite with the surrounding air to increase speed and reduce fuel consumption. However, the present invention provides an improved helicopter blade pitch control apparatus that affords advantages over the prior art. Various issued patents relate to helicopter constructions and blade constructions. The following table lists various patented helicopter constructions.
TABLE I ______________________________________ PRIOR PATENTS PATENT NO. INVENTOR ISSUE DATE ______________________________________ 2,372,481 Gagas 3-1945 2,389,798 Main 11-1945 2,443,393 Landgraf 6-1948 2,581,773 Stalker 1-1952 2,670,804 Campbell 3-1954 2,973,815 Szyncer 3-1961 4,669,958 Peyran et al 6-1987 2,456,485 Bendix 12-1948 2,404,522 Nemeth 7-1946 3,156,302 Jordan 1964 2,949,965 De Tore et al 1960 2,684,722 Perry 1954 2,494,217 Watson 1950 2,700,424 Campbell 1955 2,944,610 Gluhareff 1960 2,689,011 Zakhartchenko 1954 3,074,487 Derschmidt 1963 350,030 Bruno et al (ITALY) 7-1937 446,509 Billing (GREAT BRITAIN) 4-1936 ______________________________________